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Finding the Fourth Proportional to 518.70, 778.21 and 210.80

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Solution

The fourth proportional to 518.70, 778.21 and 210.80 is: 316.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.70 : 778.21 = 210.80 : x
  2. Step 2: Convert to fraction form
    518.70/778.21 = 210.80/x
  3. Step 3: Cross multiply
    518.70x = 778.21 × 210.80
  4. Step 4: Simplify right side
    518.70x = 164,048.09
  5. Step 5: Solve for x
    x = 164,048.09/518.70
  6. Step 6: Final answer
    x = 316.27

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.